INTRODUCTION: Superior vena cava (SVC) syndrome is a rare clinical disorder associated with obstructing venous outflow through the SVC. Although the most common cause is mediastinal tumors, the growing number of implantable cardiac devices proce dures has resulted in more patients with SVC syndrome of non-malignant etiology. DISCUSSION: It has been shown repeatedly that the use of cardiac implantable electronic devices (CIEDs) improves the quality of life of patients with symptomatic arrhythmias and reduces the mortality of patients at risk of sudden cardiac death, but the risk of complications also exists. CONCLUSION: The most common finding in patients with cardiac devices is asymptomatic venous thrombosis, but serious complications, including SVC obstruc tion should always be considered. The rapid identification of clinical symptoms and the implementation of appropriate measures are a key to preventing the morbidity and mortality of the patients. JRCD 2018; 4 (1): 5–8